im running a pretty basic sony 12" setup...two 12s and one amp. but some how this has killed my car's computer twice. the first time it happened the mechanic said that he thought a power surge fried the computer. which i was confused by because the amp draws from the battery and the alternator. so i was wondering if a capacitor would prevent this from happening in the future.
A capacitor will only work if you have the alternator to support it and the amperage draw of your system.The capacitor adds a load on the alternator as well.
Get all your electrical connections checked, both at the battery, alternator, computer, amp, etc. a capacitor does not add a load to your alternator, it is a simple short term storage, when you have a big bass hit the capacitor covers the short fall of your battery/alternator... if your headlights flicker/dim a bit when there is lots of bass then a capacitor will help with that but your cars computer should have a pretty robust power supply in it with filtering caps and diodes to prevent anything happening to it... check the voltage while your car is off, while its at idle and while driving with the revs up... off it should be 12.5V, idle anywhere between 13-14 volts and driving at least 13.8 or above, depending on what you have on in the car...
"a capacitor does not add a load to your alternator"
Are you kidding?How does the capacitor become filled with juice?Is there some magical force that automatically gives the capacitor the ability to filter and smooth current draw through some sort of solar panel?The funny thing is...they tell you to charge the cap before using it.So if it doesn't add a load to the alternator how can it help out the amperage draw?It takes power to make power,plain and simple.You can't get something for nothing.If capacitors didn't add a load on my alternator then I'd just get 140 pounds of capacitors instead of the monstrous batteries that I'm running.Stuart,either set me straight or be quiet.
dont take it personally mate but you are wrong, using such technical terms as 'juice' shows your lack of basic electrical knowledge... yes at the instant you charge a cap it is taking some energy, but once the cap is at the supply voltage it is not using any energy, it is simply holding onto it. a load in any system is something that uses energy correct? hence speakers move, amps get hot, etc. a capacitor is vitrually a lossless TEMPORARY storage device, it is used to filter out short quick dips in the power supply to the amp. They do not move, they do not get hot, they do not use energy. The reason you need to charge a cap slowly from its initial empty state, and discharge it slowly from its charged state, is because they will charge up very quickly (almost like a short) and you will get an arc which is not good for the terminals, and charging or discharging a cap too fast is bad for them as well.
there is no magic, simply sound electrical theory that has been around for oh... 200 years..
sooo... if i add say 4 million 1 farrad caps to my car, and they sit there, charged at the 12.5V... where is the load? can you show me why they will be drawing power?
Your alternator produces 14.4 volts and is the source of power for the electrical system. Current flows from the alt to the 12.5 volt battery until it is charged. (or capacitor, since it is another device that stores energy, like a battery). When your amp draws current, the capacitor will discharge, and then recharge by drawing current from the alternator. Problem is the caps designed for car audio don't store anywhere near enough energy to make any meaningful difference. One good battery stores WAY more than enough energy for an audio system, as long as the alternator can produce more power than the system can draw, and keep the battery charged.
The capacitor works the same as a battery, except it doesn't store anywhere near any much energy. It stores energy, and to recharge it draws current from the alternator. At least I think thats what Rob meant.
finally a real response that makes sense, thank you! (i mean that honestly and not sarcastically)
I still think they help to filter out flicker or dimming though, it does depend on each individual set up as every one is different...
im not trying to step on any toes here, i know im a newbie to this forum but for something as complex as car audio can be i dont think simple answers are always the best...
"I still think they help to filter out flicker or dimming though, it does depend on each individual set up as every one is different..."
They actually "smoothen" out the current that's being sent through the amps in short bursts.Caps can work in a musical environment because your amplifiers are not constantly drawing which in turn allows your cap or caps to become saturated.If you're running a tone through your vehicle and you kill your batt bank(assuming it's charged over 12volts) you're going to see dimming again instantly no matter how many caps you have.You know what fixed my problem with light flicker?A 300 ampere alternator,raised engine idle ,2 Kinetik HC2400 batteries and multiple runs of 1/0Awg power and ground wire.I'm running 6,000+watts RMS off of mono amplifiers alone.Then we need to factor in the vehicles practical needs or "normal" needs plus an amp for speakers and it all adds up to insane amount of current draw.When I burp a test tone I see voltage drop to the point of lights flickering a bit but I can play music as loud as I want and see my voltage drop down to 13.1 but I might just run a ridiculously sized capacitor and make a before and after video,with the install of the capacitor installed just to show people what's up.Nice attempt Stuart but sometimes when you're wrong you have to sit back and analyze things again and see why people are calling you out.There are plenty of things that I don't know but I try to learn about them before I go and preach my knowledge to the choir.
like i said, every setup is different, you have a massive stereo, the OP doesnt, you cant rule out caps for a small system like the OP has. Id like to see the ridiculously sized cap video, seriously im interested in seeing your setup as well... having a HO alternator, large cable runs and big batteries makes your system completely different...
like i said, not trying to step on toes, chill out and dont be so pissy lol
It's not about being pissy Stuart,it's about giving people the right information that's all.Anyhow,what are you running in your vehicle Stuart?Oh and I was speaking of a hybrid "100 Farad" capacitor or something of that size to see if it improves voltage drop at peaks in music.It'd be pretty cool to show people that caps actually do work when used properly in a video don't you guys think?
I know this is an old thread but with my last system, I had a cheap Profile AP1000M amp and a Kicker 12" cvr 4 ohm dvc and a Tsunami 10 Farad cap with all 4ga wiring and my lights still dimmed with only 500 watts. My old alt was 70 amps max (stock) and I guess a normal battery. Point is, I thought a nice big 10 Farad cap would solve the problem with my lights dimming and it only helped it, it did not solve the problem. But now, with my two Memphis class d amps and my 180 amp alt and a Kinetik 1800 battery, I have no light problems and I have another Kicker cvr 4 ohm. My voltmeter shows a constant 14.3-14.9 volts with engine on and 12.8-13.4 on battery. No need for a cap now! Just get a decent charging system and you don't need a cap.
